JS.Twettir is a worm that exploits a bug in the Twitter messaging client. Basically, JS.Twettir performs a cross-site scripting attack, attempting to spread by infecting other users profiles. Once the user views the infected account, he gets infected as well, because JS.Twettir executes and injects a JavaScript code in the viewers profile automatically. JS.Twettir also sends such or similar notifications to all contacts that contains any of the following lines:

We might be affiliated with any product we recommend on the site. Full disclosure in our Agreement of Use. By Downloading any provided Anti-spyware software to remove JS.Twettir you agree to our privacy policy and agreement of use.

Reimage is recommended to uninstall JS.Twettir. Free scanner allows you to check whether your PC is infected or not. If you need to remove malware, you have to purchase the licensed version of Reimage malware removal tool.